Apparatus for saturating absorbent sheet material



y 1936' r J. w. PEARL ,040,529

APPARATUS FOR SATURATING ABSORBENT SHEET MATERIAL Filed Aug. 26, 1933 QQ 2 3 //26 S S S S F A A A Y X I 6 6 6 5 6 29 egcgegegg 30 e s e c e INVENTOR John 14. Pear BY j L ATTORNEY Patented May 32, 1%36 UNITED STATES APPARATUS FOR SATURATING ABSORBENT SHEET MATERIAL John Wesley Pearl, Yeadon, Pa., assignor to The Barrett Company, New York, N. Y., a corporation of New Jersey Application August 26,

3 Claims.

This invention relates to saturators and more particularly to saturating kettles for impregnating absorbent fibrous sheet materials, such as roofing felt, with a liquid saturant such as asphalt, coal tar, or coal tar pitch.

One object of this invention is to provide a type of kettle roll for saturating kettles which offers improved support for the sheet material being saturated.

Another object of this invention is to provide an improved apparatus for impregnating absorbent sheet material with hot saturant in which weaving of the sheet during its passage through the apparatus is effectively prevented.

Another object of this invention is to provide a kettle for saturating sheet roofing with hot bituminous material in which special kettle rolls are provided. The rolls are designed to remove foam and excess saturant from the surface of the sheet thereby preventing lateral floating or slippage of the sheet during its passage over the rolls.

Other objects and advantages will appear from the following detailed description of my invention.

It is common practice at the present time to saturate absorbent fibrous sheet material, such as sheet roofing felt, by passing the sheet material several times in and out of a bath-of hot saturant contained in a suitable tank or kettle. This is done by looping the sheet over a plurality of kettle rolls or guide rolls disposed above and below the surface of the saturant in the tank. Contact of the hot saturant with the sheet, however, causes moisture which is generally present in the sheet, to vaporize and form steam. The steam and other gases present in the sheet which have been driven out by the hot saturant, combine with the saturant to produce a foam or froth on the surface of the sheet and on the surface of the kettle rolls. This foam forms an anti-friction film on the surface of the kettle rolls and sheet which prevents actual contact of the sheet I with portions of the kettle rolls, especially the kettle rolls above the surface of the saturant in the tank. Hence, as the sheet passes through the saturator it frequently floats laterally or side slips during its passage over the rolls. Slipping or weaving of the sheet causes an uneven tension on one side of the sheet and often results in ruptiu'es or breaks during passage of the sheet through the kettle.

In accordance with the present invention, weaving or side slipping of the sheet is prevented 1933, Serial No. 686,947

by removing the foam and excess saturant from the surface of the sheet as it passes over the rolls thereby destroying the cushioning effect of the film and providing improved traction between the sheet and the rolls. This is preferably accom- 5 plished by the use of hollow perforated kettle rolls open at both ends. Other types of rolls which remove the film of foam and excess satu rant from the surface of the sheet may also beused.

A substantial economy is efiected by the use of this invention since much less labor and supervision is required in operating saturating kettles than has heretofore been necessary. Furthermore, time and money are saved through the pre- 15 vention of rupture or breaking of the sheet.

For a better understanding of the invention reference should be made to the accompanying drawing wherein is shown, by way of illustration,

a preferred embodiment of this invention and 20 in which:

Fig. 1 is a side elevation of a saturating apparatus embodying this invention, the saturating tank being shown in section;

Fig. 2 is an enlarged view, partly in section, 25 showing a kettle roll constructed in accordance with this invention;

Fig. 3 is a sectional view taken along the line 33 of Fig. 2;

Fig. 4 is a corresponding sectional view of a 30 modified form of the invention.

Referring to the drawing with particular reference to Fig. 1, numeral 2 indicates an absorbent fibrous sheet such as the usual roofing felt passing over a guide roll 4 into a saturating kettle indicated generally by the reference numeral 6. This kettle may comprise the usual rectangular tank 8 made of sheet steel or other suitable material and adapted to hold cementitious waterproofing composition, such as heated asphalt or other fluid 40 bituminous material, utilized for the impregnation and saturation of roofing felts.

In a manner well known in the art, the saturating tank 8 is provided with a series of lower kettle rolls or guide rolls |0l0 and a set of 45 upper kettle rolls or guide rolls |2-l2. Rolls ll], of which there may be any desired number, are arranged in a spaced horizontal row near the bottom of the tank 8, so that in operation they will be a considerable distance below the level of the 50 saturant in the tank indicated by line l4. These rolls may be the ordinary smooth-surfaced cylindrical type fixed on freely-rotatable shafts I6 mounted in suitable bearings.

Upper kettle rolls ll are arranged in a horisontal row near the top of the tank in staggered relation to the lower kettle rolls l0, and are set on freely-rotatable shafts il mounted in suitable.

bearings. These rolls are preferably a considerable distance above the surface ll of the saturant in the tank. The upper kettle rolls i2 in accordance with this invention, as hereinafter pointed out, are designed and constructed to prevent weaving or slipping of the sheet passing thereover.

Numerals l8 and It denote a pair of squeeze rolls which may be driven at any desirable speed by a suitable drive (not shown). These rolls draw the fibrous sheet 2 from the source of sup ply, propel it through the saturating tank, and squeeze excess saturant from the sheet as it between them.

Although four upper kettle rolls I! are shown in Fig. l of the drawing, only one will be described in detail since all the rolls l2 shown in the drawing are of like construction. As shown in Figs. 2 and 3, each roll l2 comprises a hollow cylindrical-shaped shell 22 open at both ends, and provided with a plurality of perforations or holes 24 which may be arranged in parallel rows spaced at short intervals around the periphery of the shell. Each row of holes extends approximately the entire length of the shell, the holes in alternate rows being in staggered relation. These holes may be circular, as shown in the drawing, or they maybe triangular, square, or otherwise shaped. The shell is fixed to the rotatable shaft ll, passing axially therethrough, by means of wheel-shaped supports 26 fitted into both open ends of the shell. Each support comprises a circular rim 28 welded or otherwise attached to the interior of the shell, a hub 28 keyed or otherwise fixed to this shaft i1, and a series of spokes or webs Ill connecting the rim with the hub.

The operation of the apparatus is as follows:

A sheet of absorbent fibrous material, which may be the usual roofing felt made of rag fiber, paper stock, or other fibrous material, with or without suitable fillers as well known in the art, is led from the usual paper making machine or other source of supply over feed roll 4 into the saturating kettle 8 containing a bath of molten hot asphalt or other saturant which is maintained in a molten condition by suitable heating means, such as a steam coil associated with the kettle I. As soon as the absorbent sheet is immersed in the saturating bath, the hot saturant begins to enter the pores of the sheet. Moisture contained in the sheet is vaporized, the steam thus formed passing from the sheet and, together with the air leaving the sheet, causing the formation of foam in the bath and on the surface of the sheet.

After passing under the first lower kettle roll III, the partly impregnated sheet is led out of the bath and looped over the first upper kettle roll I2. As the sheet contacts with upper roll II, the foam, steam, oily vapors, and excess saturant adhering to the sheet leave the sheet and pass through the perforations or holes 24 into the interior of the hollow shell. The steam and oily vapors escape therefrom to the atmosphere while the liquid portion of the foam and the excess saturant drain from the open ends and holes in the shell back into the saturating tank. The removal of these film-forming materials from the surface of the sheet permits intimate contact between the sheet and the roll thereby prevent- 8 ppase between the two which has heretofore resulted in weaving and often rupture of the sheet.

After passing over the first upper roll I2 in the series, the partly impregnated sheet is led back into the bath and passed alternately under each of the remainder of lower kettle roll Ill and over each of the upper kettle rolls I! in a series of loops. In this way the sheet is alternately immersed in the hot saturant and exposed to the atmosphere until the impregnation is complete. The completely saturated sheet is withdrawn from the saturating tank and passed through squeeze rolls II and I9. These rolls, which may be driven at any desirable speed, not only pull the sheet from the source of supply over the kettle rolls in the saturating tank, but also press any excess saturant from the saturated sheet and allow it to drain back into the saturating tank.

After passing through the squeeze rolls the saturated sheet may be sent through a looping device (not shown) to allow the saturant to cool and dry and to thoroughly impregnate the fibrous sheet. The dried impregnated material may be used as a waterproof covering, or may be further treated to form coated and surfaced roofing elements or sheet roofing in a manner well known in the roofing art.

It will. be noted that the saturating kettle and kettle rolls of this invention are simple in design and construction. The improved kettle rolls destroy the cushioning effect of foam and excess saturant on the sheet being saturated and provide improved traction or contact between the sheet and the rolls. As has been pointed out above, a considerable economy is efiected by this invention since the operation requires less labor and supervision than has heretofore been required and eliminates delays for repairs or adjustments. Furthermore, loss of material through breakage or rupture of the sheet is minimized if not entirely eliminated.

Although, as described above, all of the upper kettle rolls are preferably constructed in accordance with this invention, it should be understood that only one or more of the rolls may be so constructed.

Similarly, although in most cases it is necessary to use the perforated rolls only in the upper series of guide rolls in the kettle, it is obvious that they may be used in the lower series also.

Instead of using a perforated roll, as described above, other types of rolls may be used to eliminate the foam and excess saturant from the surface of the sheet. A roll having its exterior surface provided with alternate raised and depressed areas may be employed, the raised areas supporting the sheet and the depressed areas serving as channels or drains for the removal of the saturant and foam. For example a fiuted roll or a corrugated roll, such as shown in Fig. 4, in which the corrugations are identified by the reference numeral 32, may be employed.

Since certain other changes in carrying out the process and in the constructions set forth may be made without departing from the scope of this invention, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. In apparatus for impregnating absorbent sheet material with saturant, the combination comprising a tank for holding the saturant, guiding means in sand tank positioned below the surface of said saturant for guiding the sheet material in its passage through the saturant, a kettle roll positioned above the surface of the saturant and constructed and arranged with respect to said guiding means so that sheet material passed successively under said guiding means, over said kettle roll and under said guiding means is repeatedly immersed in and emerges from the saturant during the impregnating operation, and drains in the surface of said kettle roll for removing excess saturant and foam from the surface of the sheet between immersions to prevent side slipping of the sheet as it passes through the tank.

. 2. In apparatus for impregnating sheet roofing felt withrmolten bituminous material, the combination comprising a saturating tank for holding the molten bituminous material, a series of rolls in said tank below the surface of said bituminous material, a series of hollow rolls positioned above the surface of said bituminous material having a plurality of holes in the surface thereof whlch permit liquid to drain to the interior of the rolls and thence back into the tank, said felt sheet passing alternately under mils of said first series and over rolls of said second series during the impregnating operation, said holes functioning to drain excess foam and saturant from said felt as it passes over said second series of rolls to remove foam and excess saturant from the sheet, thereby preventing side slipping of the felt as it passes through the saturating tank, and a pair of squeeze rolls between which the sheet is passed after emerging from the tank.

3. In apparatus for impregnating absorbent sheet material with saturant, the combination comprising a tank for holding the saturant, guiding means in the tank positioned below the surface of the saturant for guiding the sheet material in its passage through the saturant, a roll positioned with respect to said tank and the guiding means therein so that said sheet material passes successively over said roll and under said guiding means, said roll having aninterrupted surface to prevent weaving and sideslipping of the sheet as it passes into and through the saturant.

JOHN WESLEY PEARL.

CERTIFICATE OF CORRECTION.

Patent No. 2,040,529. May 12, 1956.

JOHN WESLEY PEARL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, second column, line 74, claim 1 for the word "sand" read said; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 25th day of August, A. D. 1936.

Leslie Frazer (Seal) Acting Commissioner of Patents. 

